src/mg_biome.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2010-2013 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "mg_biome.h"
  21 #include "gamedef.h"
  22 #include "nodedef.h"
  23 #include "map.h" //for ManualMapVoxelManipulator
  24 #include "log.h"
  25 #include "util/numeric.h"
  26 #include "main.h"
  27 #include "util/mathconstants.h"
  28 #include "porting.h"
  29
  30 const char *BiomeManager::ELEMENT_TITLE = "biome";
  31
  32 NoiseParams nparams_biome_def_heat(50, 50, v3f(500.0, 500.0, 500.0), 5349, 3, 0.70);
  33 NoiseParams nparams_biome_def_humidity(50, 50, v3f(500.0, 500.0, 500.0), 842, 3, 0.55);
  34
  35
  36 ///////////////////////////////////////////////////////////////////////////////
  37
  38
  39 BiomeManager::BiomeManager(IGameDef *gamedef)
  40 {
  41         NodeResolver *resolver = gamedef->getNodeDefManager()->getResolver();
  42
  43         np_heat     = &nparams_biome_def_heat;
  44         np_humidity = &nparams_biome_def_humidity;
  45
  46         // Create default biome to be used in case none exist
  47         Biome *b = new Biome;
  48
  49         b->id             = 0;
  50         b->name           = "Default";
  51         b->flags          = 0;
  52         b->depth_top      = 0;
  53         b->depth_filler   = 0;
  54         b->height_min     = -MAP_GENERATION_LIMIT;
  55         b->height_max     = MAP_GENERATION_LIMIT;
  56         b->heat_point     = 0.0;
  57         b->humidity_point = 0.0;
  58
  59         resolver->addNode("air",                 "", CONTENT_AIR, &b->c_top);
  60         resolver->addNode("air",                 "", CONTENT_AIR, &b->c_filler);
  61         resolver->addNode("mapgen_water_source", "", CONTENT_AIR, &b->c_water);
  62         resolver->addNode("air",                 "", CONTENT_AIR, &b->c_dust);
  63         resolver->addNode("mapgen_water_source", "", CONTENT_AIR, &b->c_dust_water);
  64
  65         add(b);
  66 }
  67
  68
  69
  70 BiomeManager::~BiomeManager()
  71 {
  72         //if (biomecache)
  73         //      delete[] biomecache;
  74 }
  75
  76
  77
  78 // just a PoC, obviously needs optimization later on (precalculate this)
  79 void BiomeManager::calcBiomes(s16 sx, s16 sy, float *heat_map,
  80         float *humidity_map, s16 *height_map, u8 *biomeid_map)
  81 {
  82         int i = 0;
  83         for (int y = 0; y != sy; y++) {
  84                 for (int x = 0; x != sx; x++, i++) {
  85                         float heat     = (heat_map[i] + 1) * 50;
  86                         float humidity = (humidity_map[i] + 1) * 50;
  87                         biomeid_map[i] = getBiome(heat, humidity, height_map[i])->id;
  88                 }
  89         }
  90 }
  91
  92
  93 Biome *BiomeManager::getBiome(float heat, float humidity, s16 y)
  94 {
  95         Biome *b, *biome_closest = NULL;
  96         float dist_min = FLT_MAX;
  97
  98         for (size_t i = 1; i < m_elements.size(); i++) {
  99                 b = (Biome *)m_elements[i];
 100                 if (!b || y > b->height_max || y < b->height_min)
 101                         continue;
 102
 103                 float d_heat     = heat     - b->heat_point;
 104                 float d_humidity = humidity - b->humidity_point;
 105                 float dist = (d_heat * d_heat) +
 106                                          (d_humidity * d_humidity);
 107                 if (dist < dist_min) {
 108                         dist_min = dist;
 109                         biome_closest = b;
 110                 }
 111         }
 112
 113         return biome_closest ? biome_closest : (Biome *)m_elements[0];
 114 }